Rubbery copolymers of (trifluoromethyl) vinyl aromatic compounds



Patented my to, 1949 RUBBERY COPOLYMERS or (TmFLUonomn'rnrmvmvr.AROMATIC COMPOUNDS Mary w. Renoll, Dayton, Ohio, assignor to no.. santoChemical Company, St. Louis, Mo.. a corporation of Delaware No Drawing.Application April 15, 1944, Serial No. 531,284

' l The present invention relates to rubbery copolymers of butadiene orbutadiene compounds with (trifluoromethyl) vinyl aromatic compounds andto a method of producing the same.

pounded, being very compatible with the ordi- 9 Claims. (01. 260-74)narily employed vulcanizing chemicals. Of great technical importance isthe easy workability of mynew. rubbers; they may be readily milled withequipment generally employed for milling and This invention has as anobject the provision 5 otherwise working natural rubber. The present ofuseful, new rubber-like products. Another copolymers have veryrgoodelasticity and excelobject of the invention is the preparation of new,lent aging properties. The compounded and vuleasily milled, syntheticrubbery copolymers pos- 1 canized copolymers are highly suitable for thesessing improved stress-strain characteristics. production of automobiletires, rubber footwear,

These and other objects which will be hereinl rubber-coated wearingapparel. electrical insulatafter disclosed are provided by the followinging compositions as for coating .wire, etc. They invention wherein thereareprepared interpolyare also readily extruded or drawn into flexiblemers of butadiene compounds and a (trifluorofibers. methyl) vinylaromatic compound, either in the I prepare my new, synthetic rubbers bypolypresence orabsence of other polymerizable mate- 1 merization,preferably in emulsion, of a mixture rials. For the preparation of mynew, rubber-like 7 containing a butadiene compound and from, say,

' products I use-as the diolefinic constituent a 2% to 50% by weight ofthe mixture of one or compound having the structure: more of theabove-mentioned (trifluoromethyl) vinyl aromatic compounds. Particularlyvaluable CHLCR'CR' 29 products are obtained by using from to 30% whereinR and R. are memb rs of th group conof the trifluoromethyl compound,based on the t g f hydr chlorine or t yl. 1. e., butatotal weight of themonomeric mixture. The (118118, isopl'ene, chloroplene,2,3-dimethy1butacopolymers obtained from one of the above mendiene,2,3-dichlorobutadiene. As the (trifiuorotioned trifiuoromethyl compoundsand a chlorinemethyl) vinyl aromatic component of my .new 20 containingbutadiene compound such as chlorocopolymers I employ a compound havingthe genprene or 2,3-dichlorobutadiene are characterized eral formula: 1by extremely high resistance to heat.

I CH2:CH.A1'.CF3 The invention is further illustrated, but no wherein Aris an aromatic hydrocarbon radical. by the following examples: Asillustrative of compounds having. the above 30 Example 1 formula may bementioned: meta-(trifluoromethyl) styrene, ortho- (trifluoromethyl)styrene, 100 a s of a mixture consisting of 5 Parts bypara-trifluoromethyl) styrene, 1 (trifluoromethweight of butadiene and25 parts by weight of yl)- 3-vinylnaphtha1ene, 1-'-(trifiuoromethy1)-4-meta-(trifluoromethyl)styrene was agitated for vinylnaphthalene,.l-(trifl-uoromethyl) -2 vinyl- 22hours at a temperature of 50 C. in asystem, naphthalene, 4 (trifluoromethyl) 4-vinylbiheld at a pH ofapproximately 7.1 andconsisting phenyl, etc. Compounds having the abovegenof 085 gram of monosodium phosphate, 9.0 grams eral formula form thesubject of my copending O disodium phosphate, 4.4 grams o a Wettingapplication, Serial No. 531,283 filed, April 15, 1944, agent known tothe trade as Santomerse :D" now Patent 2,414,330 assigned to the sameas- 40 (an alkylbenzene sulfonate), 0.5 gram ofdodecylsignee as thepresent application, mercaptan, 0.5 gram of potassium persuliate and{The present copolymers are soft, elastic, rub- 180 grams of water. Atthe end of this time, 2 her-lik material whi h may b compounded grams ofan antioxidant-such as fSantoflex B" like natural rubbers andsubsequently vulcanized (a reaction p t of ph yl nd c t hard productswhich possess mechanical prgptone) was added to the product and thelatex erties that surpass those of such prior synthetic was oas d' withan aqueous solution of s rubbers as butadiene-styrene copolymer obutafu'ric acid and sodium chloride. There was thus diene-acrylonitrilecopolymer. My new copolyobtained a 66% yield ofa soft, tacky, rubberymers are easily processed and readily commaterial, which was thenprepared for processing by washing free of emulsifier and drying for 16hours at a temperature of 45 0. and a pressure 01 2 mm. of mercury.

100 parts of the purified copolymer thus obtained was compounded with 40parts of a carbon Example 2 v This example shows the eflect ofmeta-(trifluoromethybstyrene on aging properties of ternary copolymersprepared from monomeric black, 3 parts of zinc oxide, 1 part of stearicacid, 5 mixt ures containing varying proportions of buta- 1.'I5 parts ofsulfur and 1.2 parts of a rubber vuldime Styrene meta(trifluommethy1)sty canization accelerator known to the trade as renecopolymerization of the three dmerent Santocure" (a condensation productof mercap monbmeflc mixtures containing these tobenzothiazole withcyclohexylamine) and the ponents m the proportions given below w'compounded material was cured by heating it for meted by the emulsionprocess described in v60 minutes at a temperature of 142 C. The fol-Example 1' and the respective products were lowing evaluation data wereobtained for the washed dried mmpbunded and cured as in cured product,before and after aging for 24 hours Exampie 1 E'vamauons of the curedproducts in circulating air a temperature of 100 r before and afteraging for 24*hours in circulating Before Mm air at a temperature of 100C. gave the follow- Aglng Aging ingdata:

iti'sie iitiiitat;2:::::::::::::::::::::::::::1 2,32% 2,423eopolymercomt Tensilesmglh t iiofi' Yttiglis's Modulus of Elasticity (at300% eionga- 705 1,510 Butt 2 Elongation per cent e90 410 Trifluqr IFu'estone Plasticltyseconds 2 ar lgx fir Before After Before m V WLpercent Aging Aging Aging Aging The above values for tensile strengthwere de- Wt termined on the Scott tester, according to the 2 proceduredescribed in the January 25, 1'930, 35 15 10 2,340 2,725 530 425 issueof Rubber Age. Plasticity measurement ,2 5g, g, 122% 21%; 253 32 wasmade in a Firestone plastometer, using 10 7 22 2- 1, 2,110 44 8 poundsof air pressure at a temperature of 82C.

For ur o of comparlson a butadienecu lhese results were obtained for 90minute, instead of 60 minute styrene copolymer (75:25) was prepared bythe emulsifying procedure herein shown, purified, As shown in Example 1,in styrene-butadiene and then compounded and'cured as describedcopolymers having a butadiene content of 75% above for the presentbutadiene-meta-(trifluorov the tensile strength decreases considerablyupon methyl) styrene copolymer. Evaluation of the aging and is below2,000 p. s. i. even before aging. resulting compounded and curedbutadiene- That inclusion of (trifluoromethyDstyrene in styrenecopolymer by the testing procedures emamounts as low as 2.5% results inthe production ployed above gave the following values: of a copolymerwhose tensile strength after aging is considerable above 2,000 p. s. i.is shown in the Bears After 40 above table. Aging M1118 While theproduction of my new, rubbery copolymers, as shown in the above exampleshas fig g ggff 'g 1 & 3 been described specifically by polymerization inYoungs Modulus oiE lasticity (at 306%i6n' li 1:015 5 emulsion. otherpolymer ing methods m y be fggggper cent 420 m employed, for example;polymerization in the Firestone Piasticitmseeonds presence of sodium orboron trifluoride, as will be apparent to those skilled in the art.Also, in- With respect to tensile strength, modulus of Stead ofemploying the emulsifying media ShWn elasticity, elongation andplasticity. the butag l lere may be employeii other expedients i;,30.525131 25351325 fstfifififi=iei ifiifeifitfi surpasses e u a 'ene-sene co er. In these respects my new, ru l iery int-game is employed thereaction product of hydrogen sulr ge g 33iisieii'filiiiiihfii2112351222332??? po ymer e ore as g. e ow es ne plasticity of my new rubbershows that of the mixture of phosphatesother buffer compmmds a e to toamass:- mistress;assesses? easeo mo 11, mac x ing'em g g g 6 mmface-active material, such as Gardinol WA, 9. Similarly valuableproducts are likewise obtainsodmm lauryl sulfate made by the du P ableby emulsion copolymerization of butadiene de 3 Company Nacconol' alkylairyl with ctither (trifiuogmethyl) -substituted vinyl 53 22 g gggf 2&2;fizgggi ggg aroma ic compoun Instead of meta-(trifluoronliethyil)styrene as lemploygd in the above giz figggggg gi g f gg g iggi ggfi 322 examp e, ere may e use ortho-(triflugggg g g gassessm ntst ammate:-rene, any one o e some 0 r uorome y I vinyl-naphthalenes or the(-trifluoromethyl) biz gka g gg may be varied over the range assessentsmetathe is? it may be w stituent of m ti bb 7 corporate into themonomeric mixtures one or new Syn e c m em, I y more additionalcomponents which are able to m butadiene mmpomds of the enter into thecopolymerizing reaction. As such 18 formula herein disclosed, p 1 addedcomponents there may be used any comprene, 2,3-dimethylbutadiene,2,3-dichlorobutapound containing at least one oleflnic double 1 diene,or chloroprene. 7 bond C:C or preferably a vinyl (-CHzCHz) pounds are:styrene, the nuclearly substituted styrenessuch as the cholor-, bromo-,or fluorostyrenes, the methyl-, ethyl-, or isopropyl styrenes, thecyanostyrenes, the amino styrenes, the nitro styrenes, or the vinylphenols; acrylic acid or derivatives thereof such as methyl or.ethylacryiate, methyl or ethyl methacrylate, acrylonitrile ormethacrylonitrile, acrylamide or methacrylamide, acrylyl chloride ormethacrylyl chloride; esters of lower aliphatic acids with vinylalcohol, for example, vinyl acetate, vinyl propionate or vinyl butyrate;vinyl halides such as vinyl chloride, vinyl fluoride; vinylidene halidessuch as vinylidene chloride of l-chloro-lfluoroethylene; unsaturatedacids or their derivatives such as maleic anhydride, chloromaleic'anhydride, maleonitrile, fumaronitrile, crotonic acid or itsderivatives such as methyl or ethyl crotonate or crotononitrile;cinnamic acid and derivatives such as ethyl cinnamate, cinnamonitrile,etc.

A great deal of latitude may thus be exercised in selecting a third oreven a fourth interpolymerizing component in the initial monomericmixture. Generally, inclusion of a (trifluoromethyl) vinyl aromaticcompound in monomeric mixtures containing butadiene as a major componentconfers simultaneously greater plasticity, tensile strength andelasticity to the final product, irrespective of the nature of otherolefinic materials that may be present in the monomeric mixture. Theratio of the individual monomers present in the monomeric mixture may bewidely varied. However, in order to assure the production of desirablerubbery materials it is recommended that at least from 2% to 30% of thetotal monomeric mixture be a (trifluoromethyl) vinyl aromatic compound(or a mixture of the same) and that at least 50% to80% of said monomericmixture be a butadiene compound. Where a third vinyl compound such asstyrene is employed it may be employed in amount varying from 5% to 30%of the monomeric mixture, the balance being butadiene.

Non-rubbery materials may be obtained from a butadiene compound and a(trifluoromethyl) vinyl aromatic compound either by employing a quantityof the trifluoromethyl compound which is in excess of, say, 60% of themonomeric mixture or by thermal polymerization in mass of any mixture ofa butadiene compound and one or more of the present (trifluoromethyl)vinyl aromatic compounds in the presence or absence of a catalyst. Suchnon-rubbery copolymers are hard, resinous masses which may be employedin the plastic and coating industries, as adhesives in the production oflaminated products, as wire coating resins, etc.

It is to be understood that the foregoing detailed description is givenmerely by way of illustration and that many variations may be madetherein without departing from the spirit of the invention.

What I claim is:

1. An interpolymer of between 2% and 50% of ar-(trifluoromethyDstyrene,the balance being butadiene.

ar-(trifluoromethyl)styrene, 5% to 30% of another vinyl aromaticcompound, the balance being butadiene.

3. An interpolymer of 75% butadiene, 15% of styrene and 10% ofmeta-(trifluoromethyl) styrene.

4. An elastic vulcanizable copolymer of ar- (trifluoromethyhstyrene andbutadiene, said copolymer containing from 2% to 50% 01' interpolymerizedar-(trifluoromethyDstyrene.

5. A copolymer of from two to 50 percent by weight of the polymerizablemonomers oi. a compound having the structural formula:

rsc-R"-cH=crn wherein R" is a dival'entaromatic hydrocarbon radical, anda compound of the structural formula:

. CHr=( !-=CHa wherein R and R are radicals of the group consisting ofhydrogen, chlorine and methyl.

6. A copolymer of from 2 to 50 percent by weight of a compound havingthe structural formula:

FsC*-R"CH=CH2 wherein R" is a divalent aromatic hydrocarbon radical, andthe balance of a compound having the structural formula:

CHFl J(E=CH: wherein R and R' are radicals of the group consisting ofhydrogen, chlorine and methyl.

7. A copolymer of from two to 50 percent by weight of a compound havingthe structural for mula:

Faccrr=cm wherein R" is a divalent aromatic hydrocarbon comprisessubjecting a mixture of from 2 to 50 percent by weight of a compoundhaving the structural formula:' f

Fae- "CH=CH2 wherein the R" is a. divalent aromatic hydrocarbon radicaland a compound of the structural formula: I

wherein R and R are radicalsof the group consisting of hydrogen,chlorine and methyl to a temperature between 30 and 80? C. and thencoagulating the resultant polymer.

9. A method of preparing a synthetic rubber which comprises preparinganaqu'eous emulsion of from 2 to 50 percent by weight of a compound.

- having the structural formula:

Fec-Ri'-cH=cH2 wherein R" is an aromatic hydrocarbon radical and acompound of the structural formula:

.R R CH|=$=C Hg wherein R and R are radicals of the group con-REFERENCES CITED listing or hydrogen, chlorlne and methyl, heatin: theemulsion to a. temperature of from 30 to i t; figggg igg are of record m80 0. ln'the presence of a peroxy compound to eflect polymerization,coagulating the emulsion, 5 UNITED STATES PATENTS and separating thecoagulated rubber. Number Nam1e Date my w mom. 2,226,809 Drlesbach Dec.31, 1940

